IEC60601-1-2第四版对电磁兼容测试的影响

本文将医疗器械电磁兼容标准YY0505-201 1与国际电工委员会起草的第四版IEC60601-1-2标准作了比较,从这两版标准的测试方法及限制变更等角度来解读该行业发展的变化需求,从而为今后电磁兼容实验室的发展做前瞻性的准备。     

IEC 61000-4-12第3版的新变化

基于IEC 61000-4-12第3版振铃波抗扰度试验标准,与IEC 61000-4-12第2版相比较,解析了标准中关于振铃波发生器和耦合去耦网络参数指标以及校准方法的变化、原因以及对测试的影响,介绍了测量不确定度的评定思路。     

IEC 60118-13新版标准解析

为了更好的了解新版IEC 60118-13标准,通过对比和分析IEC 60118-13新旧版标准,了解到新版标准的变化包括:增加新的测试方法、测试布置、符合性判定和测量不确定度的要求,删除了通用的电磁兼容要求.最后本文解析了新版标准对助听器电磁兼容测试要求变化的原因.     

IEC 68-2-5:1975标准的解读

本文详细解读了IEC68-2-5：1975标准。介绍了材料耐候性老化测试原理,包括户外老化及氙灯加速老化测试原理,从光谱的定义、光强的设定、温度及湿度控制等几个方面对IEC68—2—5：1975标准进行分析。最后指出该标准的技术局限性及建议如何执行该标准。     

解析IEC 60947-3:2020(Ed4.0)标准差异

该文介绍了IEC60947-3:2020(Ed.4)《低压开关设备和控制设备第3部分:开关、隔离器、隔离开关以及熔断器组合电器》与IEC 60947-3:2015标准的差异,阐述了IEC60947-3:2020标准相比于IEC 60947-3:2015标准增补及修改的部分,对两个标准中的技术特性要求和试验方法进行了分析...     

IEC 60601-1-2第四版标准解析

针对2014年发行的IEC 60601-1-2的第四版本,介绍了IEC 60601系列的标准结构,归纳了电磁兼容测试项目的测试等级、测试范围、性能判据等的变化,并对原因进行了分析.针对高频电刀,对测试项目的选择进行了说明,并重点解析了EFT测试.     

UL60745-1:2004与IEC60745-1:2003之间的差异

UL60745-1:2004是在IEC60745-1:2003基础上编写的,它等效采用了IEC标准的内容并做了适当的增减.文章就两者之间的总体差异作了对比,概括了它们之间的主要差异,并列表说明了其具体差异内容.     

UL60745-1∶2004与IEC60745-1∶2003之间的差异

UL60745-1∶2004是在IEC60745-1∶2003基础上编写的,它等效采用了IEC标准的内容并做了适当的增减。文章就两者之间的总体差异作了对比,概括了它们之间的主要差异,并列表说明了其具体差异内容。     

射频连接器和射频电缆国际标准提案系列报道（三）IEC61169-4：20087-16型射频连接器国际提案介绍

介绍了制定IEG 61189-4:2008标准的背景、必要性及其主要技术指标,及7-16型连接器产品的特点及其应用.为更好地执行该标准,针对一些常见问题进行了说明.     

SP800-30《风险评估实施指南》研究

分析了SP 800-30《风险评估实施指南》的版本演变过程,阐述了SP 800-30:2011对其他信息安全风险管理标准的重要性,重点解析了SP 800-30:2011的主要内容.     

空间互联网技术发展现状及趋势

空间互联网技术是人类进行航天测控、导航定位、远洋航行等空间应用的基础支撑,是实现全球互联互通的关键手段。首先介绍了空间互联网的概念及内涵、组成及结构、特点及优势等相关基础知识,接着总结了空间互联网的关键技术,然后阐述了空间互联网的发展现状和面临的问题,最后结合互联网技术发展趋势和航天应用的发展要求,对空间互联网技术的发展趋势进行了展望和预测。     

高速光纤综合通信网络平台研究

现代通信网络应能满足各种通信业务和通信容量日益发展的需求,实现话音、数据、视频、IP等业务的一体化综合交换和传输。在比较TDM、IP和ATM三种协议的基础上,提出"采用内置RPR和MPLS功能的MSTP平台"建设光纤综合通信网络平台的实现方法。MSTP采用SDH的数据帧结构,保持了SDH标准光接口、灵活分插低速信号、自愈环保护和功能强大的网管等优点,可对TDM、IP和ATM协议进行优化传输。     

TD-LTE符号间干扰和载波间干扰分析

ISI和ICI是TD-LTE系统机制固有的干扰现象,也是TD-LTE系统必须消除和抑制的问题。通过对ISI和ICI产生机制及消除方法的定性分析与理论推导,可使广大工程技术人员对TD-LTE系统有全新的认识,为其管理、维护和优化TD-LTE系统提供帮助。     

Cospas–Sarsat LEO and GEO: Satellite distress and safety systems (SDSS)

Cospas–Sarsat Low Earth Orbit (LEO) and Geostationary Earth Orbit (GEO) networks must provide enhanced service of Satellite Distress and Safety Systems (SDSS); to improve Search and Rescue (SAR) operations in all environments; and to increase safety and security at low cost for numbers of mobiles at sea, on land and in the air. This paper describes the concepts of integrated LEO and GEO space configurations in function of Cospas (space system for search of distress vessels and airplanes) and Sarsat SDSS, and SAR infrastructures. The paper also reviews satellite repeaters providing SDSS service for satellite beacons known as an Emergency Position Indicating Radio Beacons for Maritime, Personal Locator Beacons for land (road and rail), and Emergency Locator Transmitter (ELT) for aeronautical applications. Copyright © 2007 John Wiley & Sons, Ltd.     

带SIR结构新型多枝节加载双频滤波器

本文在传统λ/4阶梯阻抗谐振器的基础上,提出了一种新型的宽带双频滤波器改进设计方案。改进的滤波器增加了传输零点,此传输零点能有效的改进通带的选择性和阻带特性,且上阻带带宽很宽。结构简单,在传统类似滤波器同谐振频率基础上有效缩小了尺寸,并且设计的滤波器通带的中心频率和带宽是完全独立可控,方便我们应用到实际。工作在4.1 GHz和6 GHz两个频段,3 dB相对带宽分别为7.2%和2.2%,实测和仿真吻合良好。     

Progress in doping semiconductor nanowires during growth

The anisotropic growth of one-dimensional or filamental crystals in the form of microwires and nanowires constitutes a rich domain of epitaxy and newly enabled applications at different length and size scales. Significant progress has been accomplished in controlling the growth, morphology, and properties of semiconductor nanowires and consequently their device level performance. The objective of this review is two-fold: to highlight progress up to date in nanowire doping and to discuss the remaining fundamental challenges. We focus on the most common semiconductor nanowire growth mechanism, the vapor-liquid-solid growth, and the perturbation of its kinetic and thermodynamic aspects with the introduction of dopants. We survey the origins of dopant gradients in nanowire growth and summarize quantification techniques for dopants and free-carrier concentrations. We analyze the morphological changes due to dopants and the influence of growth droplet seeds on composition and morphology and review growth aspects and alternatives that can mitigate these effects. We then summarize some of the remaining issues pertaining to dopant control in nanowires.     

1xEV-DO与HSPA无线接入技术对比

HSPA与1xEV-DO具有相同的目的和基本相同的技术实现手段,本文主要对1xEV-DO与HSDPA从标准演进、关键技术、网络结构与性能、商用情况等方面进行了全面的对比分析。     

Towards Mobile Ubiquitous Service Environment

In this article we present a perspective on future vision of mobile communications and services which is referred to as Mobile Ubiquitous Service Environment (MUSE). Based on analysis of wireless communications and services, we exploit a conceptual model for MUSE via a top-down approach. The conceptual model consists of three major elements: Terminal Service Environment (TSE), Network Service Environment (NSE) and User Identity (UID). The concept of Always the Best Experience (ABE) is addressed as the hinge in design and development such that the user-centric services could be provided automatically and intelligently in the future diverse wireless world Based on these, we further discuss the issues on design and implementation of architecture of future wireless communication system. Requirements for architecture brought by the new features of MUSE are listed. Moreover, we also address several tradeoffs that should be taken into consideration in design. Finally, the deployment challenges for MUSE, such as reflectiveness of system, security and privacy, as well as peer-to-peer AAA are predicted.Ji Yang received PhD degree on Circuit and System, Bachelor degree on Telecommunication Engineering from Beijing University of Posts and Telecommunications (BUPT) in 2002 and 1993 respectively. Currently, he is an associate professor of BUPT, chief technical supervisor of Wireless Technology Innovation Institute, and vice manager of MTlab of Sino-Germany Software Institute. He leads the research on service and application in Future Forum in China. He also made much contribution to the China Communication Standardization Association (CCSA), including the vision of future Mobile Ubiquitous Service Environment, architecture of future B3G mobile terminal, etc. His research interests include architecture design for mobile ubiquitous networks, theory of self-organization, etc.Zhang Ping is now the professor of Beijing University of Posts and Telecommunications and director of Wireless Technology Innovation (WTI) Institute, BUPT. He has also served on the senior member of C3G Group, China MOST 863 future mobile communication FuTURE project, vice-chairman of China FuTURE Forum, and member of Vision Committee of World Wireless Research Forum(WWRF), he was vice chair of WWRF in 2005. He is also invited as the consultants for many domestic and oversea communication companies. He is very active on the international research activity on Beyond 3G area. He also participated in several European projects such as E2R and MOCCA. Until now, he has published 6 books, around 400 publications in journals and conferences in the area of telecommunications. His main research interests are theory and applications in wireless communication area. He was awarded by government, city of Beijing and Ministry of Information Industry several times for his great contribution to the industry and research activity in China.Hu Zheng is a PH.D candidate in mobile communications engineering in Wireless Technology Innovation Institute (WTI) at Beijing University of Posts and Telecommunications (BUPT). He received B.S degree from Nanjing University of Posts and Telecommunications in 2002, majoring in computer communications engineering. He currently works on serivce aspects of mobile ubiquitous communication system with focus on design and performance evaluation of interaction protocols and services in self-organized service environment.Wang Xu received the B.Tech. degree in electronic engineering from Beijing Polytechnic University (now named as Beijing University of Technology), Beijing, China, in 2002. Now he is working for his Ph.D. degree in Wireless Technology Innovation (WTI) Institute, Beijing University of Posts and Telecommunications (BUPT). His current interests include wireless communications in personal area, ad hoc networks and peer-to-peer system.Li Yinong received the BS degree major in Telecommunication Engineering in 1993 from Beijing University of Posts and Telecommunications, the MS degree and PhD degree major in Telecommunication and Electronic System in 1995 and 2003 from the Beijing University of Posts and Telecommunications. He is currently a lecture of STE (School of Telecommunication Engineering) of BUPT. His main research interests include service modeling, service composition approach, and intelligent service. In BUPT, he has given several lectures to both graduate and undergraduate students such as Information Theory, Speech Recognition, Pattern Recognition and Artificial Intelligence.     

Graphene‐Based Nanomaterials: Synthesis,Properties, and Optical and Optoelectronic Applications

Graphene, a two‐dimensional, single‐atom‐thick carbon crystal arranged in a honeycomb lattice, shows extraordinary electronic, mechanical, thermal, optical, and optoelectronic properties, and has great potential in next‐generation electronics, optics, and optoelectronics. Graphene and graphene‐based nanomaterials have witnessed a very fast development of both fundamental and practical aspects in optics and optoelectronics since 2008. In this Feature Article, the synthesis techniques and main electronic and optical properties of graphene‐based nanomaterials are introduced with a comprehensive view. Recent progress of graphene‐based nanomaterials in optical and optoelectronic applications is then reviewed, including transparent conductive electrodes, photodetectors and phototransistors, photovoltaics and light emitting devices, saturable absorbers for ultrafast lasers, and biological and photocatalytic applications. In the final section, perspectives are given and future challenges in optical and optoelectronic applications of graphene‐based nanomaterials are addressed.     

开放和分解OTN网络技术研究和分析

如何构建开放和分解的OTN网络,以实现跨厂家设备的混合组网和光层互连,一直是运营商和设备商追求的目标,ONF和LFN这两大开源项目组织分别基于各自的SDN控制平台——ONOS和OpenDayLight,给出了自己的解决方案——ODTN+TAPI和OpenROADM+TPCE,本文对这两种技术方案作了深入的研究和分析,比较了这两种技术的异同点,并对当前这两种技术的发展和应用前景作了简要的说明。